Nantucket board hears $47M–$62M design options for Easy Street flood mitigation; staff urge continued work to preserve grant momentum

Leah Hill, the town’s coastal resilience coordinator, told the Select Board on Feb. 11 that the Easy Street flood mitigation project now has three conceptual design options and a scope of additional work intended to let the town pick one design to advance to full design and permitting. “If we, meaning the town and private property owners, take no action, we can expect about $1,200,000,000 in losses and damages from now out to 2070,” Hill said.

Hill said the Coastal Zone Management grant that supported the concept phase produced an existing-conditions and flood-risk report, a concept design package and three refined alternatives. The options are: a bulkhead expansion and elevation (concept estimate a little over $47,000,000); an adaptable road raising to 6.5 feet NAVD88 (about $58,000,000); or a straight road raising to 8 feet NAVD88 (about $62,000,000). Hill emphasized the numbers are conceptual: “take these with a grain of salt,” she said, and added that cost estimates typically change as designs move from 10% toward 100% design.

The presentation laid out the project tasks staff recommend before selecting a preferred design: enhanced photorealistic graphics so residents can visualize impacts; development of a protocol to incorporate local NOAA tide‑gauge data into design flood elevations; additional coastal modeling to test each option’s performance and effects on adjacent properties; a feasibility study for a resilient pump station; a stormwater field investigation and modeling program; a FEMA benefit‑cost analysis; and a historic‑structures regulation review to advise owners of protected properties.

Hill said the town has funding from a town‑meeting article in 2025 to move a chosen design to full design and permitting, but warned that permitting can range from roughly three to seven years and construction phased around the island’s peak season could take two years. She said stopping the work now risks losing grant competitiveness and previous investment: continuing the studies, she said, preserves momentum and strengthens future grant applications.

Board members asked technical and policy questions. One member urged including local tide‑gauge trends in the models; Hill said that is covered by the proposed design‑flood‑elevation task. Members also asked whether the town would need eminent‑domain authority for larger road raises and whether an existing force main could be repurposed to move pumped stormwater to the wastewater plant; Hill said those are explicitly scoped for investigation.

Brooke Moore, speaking during the discussion, said the permitting timeline means the town cannot afford to delay: “When you just look at the timeline of permitting, we can’t afford to wait,” she said, and endorsed incremental progress paired with strong outreach and visualization. Several members backed placing the pending resiliency contracts on the next meeting agenda and running a focused downtown workshop to show stakeholders how each option would look and function.

Next steps outlined by staff include refining the preferred scope tasks, producing the photorealistic visualizations, performing targeted fieldwork and modeling, and advancing one design into 30% design and permitting with cost‑estimate updates at each design milestone. The staff presentation and the CRP (Coastal Resilience Plan) update contract are expected to return on the next meeting agenda for formal action.

The Select Board did not vote on a specific design at the Feb. 11 meeting; members instructed staff to proceed with the scoped investigative and outreach tasks so the board can make an informed decision at a later date.